This invention relates to heat exchanger assemblies comprising a water heating tank and a heat exchanger mounted therein through which a suitable thermosyphon medium is circulated from a heat collector so as to give up its heat to the water and return to the collector where it collects more heat to be transferred to the water. Preferably the medium is of the liquid-gas phase change type, such as Freon, and the assembly is employed as part of a solar hot water heating system.
In such a system it is highly desirable that the circulation of the medium proceed with the least obstruction. If the medium is passed through a heat exchanger comprising a coiled tube immersed in a tank the freedom of circulation is greatly inhibited by the restricted path and efficiency is greatly reduced. Additionally, in any such system it is important to reduce to a minimum the likelihood of contaminating leakage of the medium within the tank into the water being heated.
It is an object of the invention to provide a heat exchanger-tank assembly for use in a hot water heating system which provides maximum freedom of circulation for the medium employed and greatly improved security against leakage by eliminating the need for making any seals in the medium circulating elements once the heat exchanger has been tested and mounted in the tank, i.e., only seals on the water side being required after assembly.
The invention also includes a novel method of assembly of the several components.